History is something everyone in my Fairy Kingdom takes a huge interest in. Not only does it have direct relevance to relationships between the different groups (the dwarves and elves being the obvious example), all in the realm are aware of their world being attacked and who by and when their world is responsible for the attacking, thus provoking a violent response back again. So what wars would your fictional world have a history of and perhaps still suffers the consequences from? What wars are never discussed because your world is ashamed of its role in them?
There are history programmes on FNN (in favour of the fairy royals to nobody’s surprise). Everybody responsible for history programming takes the official line. Eileen is the nearest to a revisionist and even she takes most things as gospel. The Witch always disputed the truth of anything broadcast on FNN as she feels her family was unfairly portrayed and treated. What Eileen queried was whether the royals could’ve intervened sooner, acted more fairly, preventing the need for a forceful defence. Eileen’s queries are not welcome. They would never be welcome. But Eileen saw that as no excuse to avoid asking the awkward questions!
Do your characters question the official histories? Do they write them or their own versions? What is taught in your equivalent of schools and so on?
Your fictional world has to come from somewhere so even if you don't write about the history directly, you should know where your world "comes from" as this will feed directly into what you write and how you write it. If your world has a series of tragedies, for example, does it change its outlook on life in general (I think it would)? Would your characters have a naturally optimistic attitude or not? What history, personal or otherwise, triggers this?